-l : The name of the user will be changed from old_login_name to NEW_LOGIN_NAME. Nothing else is changed. In particular, the users home directory name should probably be changed to reflect the new login name.

NEW_LOGIN_NAME : New Login name/user-id

old_login_name : Old login name/user-id

An example

For example, change the userid vivek to new id called sradmin. You need to type the following command:# usermod -l sradmin vivek